Project Summary/Abstract Emergency departments receive a high volume of patients with opioid and other substance use disorders. As a critical point-of-entry to the healthcare system, emergency department visits may present a valuable opportunity for screening, brief intervention, and referral to treatment (SBIRT). SBIRT is an approach to substance use intervention that can be administered in general medical settings and typically includes administering a standardized substance use screening tool, providing advice about reducing substance use, setting goals, and arranging for referral to treatment as appropriate. Initial research examining the feasibility and clinical effects of SBIRT in emergency departments is encouraging, but rates of successful linkage to treatment (i.e., how many patients referred to treatment actually attend treatment intake) could be substantially improved, and existing data leave unanswered questions. For example, it is unknown how rates of successful linkage to treatment may vary for individuals with different substance use disorders (e.g., opioid, alcohol, cocaine). Other patient characteristics may also predict successes or failures in treatment linkage, including demographic variables, insurance status, psychiatric comorbidity, or the presence of other co-morbid chronic diseases. Further, prior SBIRT programs have not been tailored for individuals with opioid use disorder (OUD), and the characteristics, treatment preferences, and obstacles to treatment linkage have not been thoroughly evaluated among OUD patients in the emergency department. To address these questions, the proposed R03, Behavioral Science Track Award for Rapid Transition (B/Start) will examine data from the SBIRT program in the Emergency Department at Johns Hopkins Bayview Medical Center, which has been ongoing since July 2017. Specifically, we will use existing data extraction infrastructure at Johns Hopkins to query the electronic health record and SBIRT program records to describe rates of successful treatment linkage according to primary substance use disorder and other patient characteristics in an anticipated sample size of 2400 patients referred to treatment by the SBIRT program. In addition, we will collect survey data evaluating barriers to treatment linkage and treatment preferences among 100 OUD patients receiving SBIRT in the emergency department. These data will support future randomized controlled trials to evaluate and improve treatment linkage. Ultimately, improvement in the rate of successful treatment linkage following SBIRT should lead to better patient outcomes. If the effectiveness of SBIRT in connecting patients to treatment is improved using optimized SBIRT programs, organizations will be more likely to invest in and adopt SBIRT in settings such as emergency departments where the potential for clinical impact is high.